A leading Russian activist who campaigned against environmental damage caused by preparations for the Winter Olympics in Sochi was sentenced to three years in a penal colony on Wednesday.

Rights groups blasted the decision against Yevgeny Vitishko, a geologist and activist with the group Environmental Watch on the North Caucasus (EWNC), who has been a vehement critic of the damage to the environment from the construction of venues for the Sochi Games.

The Olympics mark the biggest event to be held in Russia since the fall of the Soviet Union but it has been marred by concerns over massive building projects in pristine wooded and mountain areas.

Vitishko was convicted in 2012 of damaging a fence during a protest against the construction of what the group believes is a mansion for the region's governor in a public forest and received a suspended sentence.

But a judge in the southern Russian city of Krasnodar Wednesday upheld a ruling that he had breached that sentence and ordered him to serve a three-year prison term.

Human Rights Watch condemned Vitishko's sentence as punishment for his criticism of the Olympics.

"The case against Vitishko has been politically motivated from the start," Yulia Gorbunova, a Russia researcher at HRW, said in a statement.

"When the authorities continued to harass him it became clear they were trying to silence and exact retribution against certain persistent critics of the preparations for the Olympics."

His NGO has "faced increased harassment by officials for exposing the destruction of areas of outstanding natural beauty to make room for the Olympic sites," Amnesty International said in a statement on Tuesday.

Vitishko was placed under arrest last Monday for 15 days for allegedly swearing in public, meaning that he was behind bars during the opening ceremony of the Sochi games.

He was also unable to make a personal appearance at the appeal hearing, instead defending himself via a shaky video link.

His lawyer Marina Dubrovina told AFP that Vitishko would most likely be taken to a penal colony immediately after his 15-day arrest runs out next Tuesday.

'A new political prisoner'

Environmental Watch on the North Caucasus has accused the Russian authorities of deliberately trying to muzzle environmental activists ahead of the Sochi games.

"Amid the 2014 Olympics, a new political prisoner has appeared, convicted on fabricated grounds for his environmental and rights activism," the EWNC said in a statement after the Wednesday verdict.

Vitishko had previously told AFP that he experienced daily surveillance and suspected that police tapped his phone.

Since November last year at least six members of the group have been detained in police cells for up to 15 days.

Pressure against the group grew after it began work on a major report on Sochi violations, which was presented Wednesday in Moscow.

The report outlined in detail the damage done by the construction of Olympic infrastructure to the Sochi National Park and other areas of significant natural beauty.

It said the region's nature was "sacrificed for the sake of the ambition of one man," referring to President Vladimir Putin.

Russian officials have dismissed most of the criticism of the Sochi preparations, with Deputy Environment Minister Rinat Gizatulin recently advising activists to "stop tying themselves to every tree."